The hybrid origin of Potamogeton biwaensis Miki, an endemic submerged plant in Lake Biwa, Japan

Lake Biwa is the largest lake in Japan, and is known to have an ancient origin. The flora and fauna of this lake are characterized by high levels of endemism. Potamogeton biwaensis Miki (Potamogetonaceae) is one of two macrophyte species endemic to Lake Biwa. In the present study, we concluded based on DNA evidence that P. biwaensis is a hybrid between P. wrightii and P. maackianus. Recently, the populations of P. biwaensis have declined, and continuous monitoring is important for the conservation of this endemic macrophyte.